[Effect of substances, absorbing ultraviolet irradiation on Bacillus subtilis resistance to inactivation and mutagenic action of natural sunlight].

Substances, absorbing UV-irradiation from sunlight (triptophan, cistein, catalase) decrease Bacillus subtilis resistance to sunlight-induced lethal and mutagenic damages. Possible, they act as exogenous photosensitizers. Tryptophan was found to be the most active photosensitizer. Cistein and catalase are not so active. Casaminoacids being present in the bacterial suspensions during illumination protect bacteria from mutagenic action sunlight. In this studies we can demonstrate, that sunlight damage B. subtilis membranes and allows substances to penetration into cells. Following, that polishing of the environmental by chemical agents can strength genetic risk for organisms permanently exposure to sunlight.